Heating systems in which a fluid is heated and then thermally circulated through a closed loop to other parts of the building are well known in the prior art. Generally such systems utilize a heat source such as a boiler that is located at a lower level of the building to heat a medium such as water for circulation through the loop. In systems of this type thermal circulation is generally utilized to circulate the heating medium with the relatively low density heated water and steam rising to the upper portions of the building where the heat can be extracted, and the relatively high density condensate flowing by gravity back to the lower level heat source for reheating.
A limitation with such heating systems is that to utilize thermal circulation to distribute the heat, the heat sources must always be located at the lower portions of the building. Some heat sources such as solar collectors or fireplace collectors generally cannot be located at the lowest levels of the building and therefore require additional mechanical apparatus such as pumps or blowers to transfer the collected heat from their level to lower levels of the building where the heat can be used or stored. The use of pumps and blowers in systems of this type not only expends considerable energy but also requires expensive equipment and controls.
Accordingly, it is an object of the present invention to provide a heating system in which heat is circulated from an elevated level of a building to a lower level for storage and distribution without additional energy or output.
Another object of the invention is to tie multiple heat collectors such as solar collectors and fireplace collectors into one integrated system that requires no external pumps or energy to move the collected heat to other parts of the building.
Yet another object of the invention is to provide a novel heating system wherein heat is collected and transferred to a lower level storage tank whenever the input temperature of the heat collectors is slightly higher than the storage tank temperature and wherein heat input into the system will follow the storage tank temperature.